The present invention relates to a security system and a method for computers connected to a network, or in particular to a security system and a method wherein a computer connected to a network normalizes its own operating condition, or more in particular to a security system and a method wherein the computer executes its own protective measure against any intrusion into the network from outside.
A firewall has conventionally been suggested for limiting access from outside a network in order to provide protection against intrusion into the computer on the network from outside. The firewall controls the access to a computer on a network according to the combination of the IP address of a source and the IP address of a destination. The mainstream of the firewall has the functions of (1) limiting the IP address capable of accessing the resources of a computer for each service of TCP (transmission control protocol) or UDP (user datagram protocol), and (2) taking the access record. In particular, Firewall-1 of Checkpoint provides not only the gateways but each computer with the function of access control, and can manage the setting of a plurality of computers with a single computer.